Group 3 :Group 3 :

1.Ainia Rohmah2.Anggre Tiara O3.Dewi Puspita4.Hajar Panca S5.Millati Azka6.Nuraini7.Setyo Aji W.W8.Toni Wijayanto

Isothermal

Isobaric

Isochoric

adiabatic

thermodynamics

definition

First law of First law of thermodynamicsthermodynamicsFirst Law of thermodynamics states that :

Whenever heat Q is given to a system, a portion of heat is used to increase its internal energy in the amount of U, whereas the remaining leaves the system when the system performs a work W to its surroundings.

Mathematically, the first law of thermodynamics is formulated by :

Q = U + W

Q>0

Q<0

W>0 W<0

W positip jika sistem melakukan usaha

W negatip jika sistem dikenai usaha

Q positip Jika sistem menerima kalor

Q negatip jika sistem melepas kalor

Energi dalam U tidak terpengaruh oleh proses, yang dilihat adalah hanya pada keadaan awal dan keadaan akhir

The first law of thermodynamics for The first law of thermodynamics for isothermal processisothermal process

At isothermal Process : T = 0, so U = 0

The work done by the isothermal process is :

,so

Q = U + W = 0 + W = W

Q =

1

2lnV

VnRTW

1

2lnV

VnRTW

The first law of thermodynamics for The first law of thermodynamics for isobaricisobaricprocessprocess

At isobaric process the pressure is constant

DP = 0

Internal energy , so

)(2

5

2

52

3

12 VVPVPQ

VPVPWUQ

The first law of thermodynamics The first law of thermodynamics for for

isochoric processisochoric process

At Isochoric process volume is constant, V = 0, so the work done W = PV = 0, its produce :

)(2

3

2

3

0

12 TTnRTnRUQ

UWUQ

The first law of thermodynamics The first law of thermodynamics for adiabaticfor adiabatic

process processAdiabatic process is a process without any transfer of heat into or from the system (Q=0)and it applies :

)(2

3

)(2

3

0

21

12

TTnRW

TTnRUW

WU

WUQ

and